Your fancy new iPhone OS 3.0 starting to look a bit long in the tooth? Heads up, Apple's now sending out the beta OS 3.1 and its SDK to the developer community to finagle with. We're still looking to see what's been changed here, so for now, if you're someone who needs the Latest and Greatest and happens to have the right access, download away!
Update: Still tinkering, but we've seen a new "Save a Copy" option for 3G S video editing that lets you retain the original film while saving an edited clip (picture after the break, thanks Kevin), as well as some reports of MMS being activated, but it seems to stall before actually being sent out over AT&T's network.